from fastapi import FastAPI, UploadFile, Request
from fastapi.responses import FileResponse, HTMLResponse
from fastapi.middleware.cors import CORSMiddleware
import os
import uuid
import time
import threading

app = FastAPI()

# CORS
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

UPLOAD_DIR = "uploads"
os.makedirs(UPLOAD_DIR, exist_ok=True)

# Store file metadata: path -> {time, original_name}
file_times = {}
file_meta = {}

# ── Serve frontend ────────────────────────────────────────────────────────────
@app.get("/", response_class=HTMLResponse)
def home():
    with open("templates/index.html", "r") as f:
        return HTMLResponse(content=f.read())

# ── Upload ────────────────────────────────────────────────────────────────────
@app.post("/upload")
async def upload(file: UploadFile):
    file_id = str(uuid.uuid4())[:8]
    # Sanitize filename — replace spaces with underscores, keep extension safe
    safe_name = file.filename.replace(" ", "_")
    file_path = os.path.join(UPLOAD_DIR, f"{file_id}_{safe_name}")

    with open(file_path, "wb") as f:
        f.write(await file.read())

    # Save upload time and original name
    file_times[file_path] = time.time()
    file_meta[file_path] = file.filename

    download_id = f"{file_id}_{safe_name}"
    return {
        "link": f"/file/{download_id}",
        "file_id": download_id,
        "original_name": file.filename,
        "expires_in": 300,
    }

# ── Download ──────────────────────────────────────────────────────────────────
@app.get("/file/{file_id:path}")
def get_file(file_id: str):
    file_path = os.path.join(UPLOAD_DIR, file_id)

    if not os.path.exists(file_path):
        from fastapi.responses import JSONResponse
        return JSONResponse(status_code=404, content={"error": "File expired or not found"})

    # Check if expired (extra safety check)
    if file_path in file_times:
        if time.time() - file_times[file_path] > 300:
            if os.path.exists(file_path):
                os.remove(file_path)
            file_times.pop(file_path, None)
            file_meta.pop(file_path, None)
            from fastapi.responses import JSONResponse
            return JSONResponse(status_code=410, content={"error": "File has expired"})

    original_name = file_meta.get(file_path, os.path.basename(file_path))
    return FileResponse(
        file_path,
        filename=original_name,
        headers={"Content-Disposition": f'attachment; filename="{original_name}"'},
    )

# ── File status endpoint (for countdown UI) ───────────────────────────────────
@app.get("/status/{file_id:path}")
def file_status(file_id: str):
    file_path = os.path.join(UPLOAD_DIR, file_id)
    if file_path not in file_times:
        return {"exists": False}
    elapsed = time.time() - file_times[file_path]
    remaining = max(0, 300 - elapsed)
    return {
        "exists": os.path.exists(file_path),
        "remaining_seconds": int(remaining),
        "original_name": file_meta.get(file_path, ""),
    }

# ── Auto-delete thread ────────────────────────────────────────────────────────
def cleanup_files():
    while True:
        now = time.time()
        for path in list(file_times.keys()):
            if now - file_times[path] > 300:  # 5 minutes
                if os.path.exists(path):
                    os.remove(path)
                file_times.pop(path, None)
                file_meta.pop(path, None)
        time.sleep(60)  # check every 1 minute

threading.Thread(target=cleanup_files, daemon=True).start()

# ── Run ───────────────────────────────────────────────────────────────────────
if __name__ == "__main__":
    import uvicorn 
    uvicorn.run("app:app", host="0.0.0.0", port=7860, reload=True)